Three classes of experimental ingredients having good high temperature stability were substituted, singly and in combination, for corresponding ingredients in a standard friction material. The effects of substitution were evaluated by physical and chemical analysis, and principally by determination of friction and wear properties as a function of temperature on a sample drag dynamometer. The major finding was the demonstration of the potential of potassium titanate fiber for the improvement of a friction material of the secondary lining type. For example, the maintenance of a mean friction coefficient of 0.35 between 232 and 343 C (450 and 650 F) was achieved in the presence of the titanate fiber, as opposed to a value of 0.30 in its absence. Wear improvement of the order of 30 to 40% also becomes possible by proper adjustment of resin content and potassium titanate fiber-to-asbestos ratio.